Seventy-one developmentally dislocated hips in 47 children with an average age of 11 months (range 4-16 months) were treated by the medial approach without opening the capsule followed by 6 months of hip spica-cast immobilization. At the latest follow-up 63 hips were rated excellent and good, and 8 hips showed subluxation. No avascular necrosis had occurred. It is concluded that this approach is safe and effective for treating developmental dislocation of the hip. Moreover, opening the capsule is not only an unnecessary task in this age group but also should be avoided to prevent avascular necrosis.